If nature does not provide man with the necessary material, it is the laboratory ____ he will turn to for it.
This problem is not worth ______ again.
Antony _____ be an actor, for he doesn’t like plays or films at all. must B. may C. can’t D. mustn’t
— Could I have a word with you, mum?— Oh , if you ______ .
He was homeless, so we took him ____.
Her mother ____ her stories patiently every evening when she was a little girl.